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91.
Sargodha district is one of the least studied regions of Pakistan regarding its ethnobotanical values. This paper is the first report related to the documentation and conservation status of the tree species in the Sargodha district, and their folk ethnobotanical uses. An interview base survey was conducted in the study area in 2010-2013. The ethnobotanical data revealed the use of 100 tree species (6 gymnosperms, 94 angiosperms) belonging to 77 genera (6 gymnosperms, 71 angiosperms) and 39 families (4 gymnosperms, 35 angiosperms), with the Fabaceae ranking first with 19 tree species, followed by the Moraceae (12 species). Tree species like Aegle marmelos, Butea monosperma, Diospyrus malabarica, Gmelina arborea, Kigelia africana, Manilkara hexandra, Manilkara zapota, Mimusops elengi, Nyctanthes arbor-tristis, Putranjiva roxburghii, Terminalia arjuna and Terminalia bellerica are not only unique in their medicinal value but also interesting because of their unusual occurrence here. Thevetia peruviana, Cassia fistula, Celtis australis, Delonix regia, Diospyrus malabarica, Grevillea robusta, Haplophragma adenophylum, Jacaranda mimosifolia, Lagerstroemia speciosa, Plumeria rubra, Pterospermum acerifolium, Roystonea regia, Taxodium distichum and Tectona grandis are included among the worth looking ornamental tree species. Capparis decidua, Dalbergia sissoo, Tamarix aphylla, Tamarix dioica, Prosopis cineraria and Ziziphus mauritiana are the most commonly used timber species. Other common ethnobotanical utilization of these trees includes either sheltering or fuel or agricultural uses. Lack of awareness about the potential uses of these species, and particularly ignorance of the concerned authorities, have led to a decline in the population of this precious tree flora. Documentation of this tree flora, and as-sociated indigenous knowledge, can be used as a basis for developing management plans for conservation and sustainable use of this flora in the study area. A well-organized management is critical to restore and conserve this endangered natural resource in the District Sargodha, Pakistan. The immense medicinal and timber value of these tree species make it necessary to promote their conservation to simultaneously alleviate the poverty and improve the socio-economic status of the study area.  相似文献   
92.
Interferon regulatory factor 5 (IRF-5) plays an important role in the innate antiviral and inflammatory response. Specific IRF-5 haplotypes are associated with dysregulated expression of type I interferons and predisposition to autoimmune disorders. IRF-5 is activated by Toll-like receptor 7 (TLR7) and TLR9 via the MyD88 pathway, where it interacts with both MyD88 and the E3 ubiquitin ligase, TRAF6. To understand the role of these interactions in the regulation of IRF-5, we examined the role of ubiquitination and showed that IRF-5 is subjected to TRAF6-mediated K63-linked ubiquitination, which is important for IRF-5 nuclear translocation and target gene regulation. We show that while the murine IRF-5 and human IRF-5 variant 4 (HuIRF-5v4) and HuIRF-5v5 are ubiquitinated, an IRF-5 bone marrow variant mutant containing an internal deletion of 288 nucleotides is not ubiquitinated. Lysine residues at positions 410 and 411 in a putative TRAF6 consensus binding domain of IRF-5 are the targets of K63-linked ubiquitination. Mutagenesis of these two lysines abolished IRF-5 ubiquitination, nuclear translocation, and the IFNA promoter-inducing activity but not the IRF-5-TRAF6 interaction. Finally, we show that IRAK1 associates with IRF-5 and that this interaction precedes and is required for IRF-5 ubiquitination and activation. Thus, our findings offer a new mechanistic insight into IRF-5 gene induction program through hitherto unknown processes of IRF-5 ubiquitination.  相似文献   
93.
CEA and innate immunity.   总被引:5,自引:0,他引:5  
  相似文献   
94.
Several species of commensal Neisseriae (Cn) may colonize the human nasopharynx, but little is known about their adhesion mechanisms. We have investigated structural and functional similarities between adhesins of Cn and of Neisseria meningitidis (Nm), also a frequent colonizer of the nasopharynx. In this study, we demonstrate the expression of Opa-like proteins in nine strains of Cn. Phylogenetic analysis segregated the majority of the Cn Opa in a cluster separated from the pathogenic cluster with a few exceptions. One Opa, which located within the pathogenic cluster, was strikingly similar (74%) to an Opa of a Neisseria gonorrhoeae (Ng) strain and, like Ng, it lacked the extra Y11 or the 136DKF138 triplet insert, which are conserved among many N. meningitidis Opa proteins. Most importantly, the majority of the Cn Opa proteins were able to interact with human CEACAM1 (CD66a) molecules, previously identified as receptors for pathogenic Opa proteins. By the use of CEACAM1 N-domain mutants, we demonstrate that Cn Opa target the same region of the N-domain of the receptor as that used by Nm. Furthermore, Cn strains bound to cell-expressed human CEACAM1. In competition assays, adherent Cn strain C450, exhibiting high affinity for CEACAM1, was not displaced by a Nm isolate and vice versa . But in simultaneous incubation, Nm out-competed the Cn strain. This is the first study to demonstrate the expression of adhesins in Cn that are structurally and functionally closely related to pathogenic adhesins. The studies imply that some Cn have the potential to occupy and thus compete with the pathogens for receptors on human mucosa, their common and exclusive niche.  相似文献   
95.
96.
Cyclic nucleotide-gated ion channels (CNGCs) are calcium-permeable channels that are involved in various biological functions. Nevertheless, phylogeny and function of plant CNGCs are not well understood. In this study, 333 CNGC genes from 15 plant species were identified using comprehensive bioinformatics approaches. Extensive bioinformatics analyses demonstrated that CNGCs of Group IVa were distinct to those of other groups in gene structure and amino acid sequence of cyclic nucleotide-binding domain. A CNGC-specific motif that recognizes all identified plant CNGCs was generated. Phylogenetic analysis indicated that CNGC proteins of flowering plant species formed five groups. However, CNGCs of the non-vascular plant Physcomitrella patens clustered only in two groups (IVa and IVb), while those of the vascular non-flowering plant Selaginella moellendorffii gathered in four (IVa, IVb, I and II). These data suggest that Group IV CNGCs are most ancient and Group III CNGCs are most recently evolved in flowering plants. Furthermore, silencing analyses revealed that a set of CNGC genes might be involved in disease resistance and abiotic stress responses in tomato and function of SlCNGCs does not correlate with the group that they are belonging to. Our results indicate that Group IVa CNGCs are structurally but not functionally unique among plant CNGCs.  相似文献   
97.

Objective

To systematically review and synthesize available epidemiological data on hepatitis C virus (HCV) prevalence and incidence in the Maghreb region and to estimate the country-specific population-level HCV prevalence.

Methods

We conducted a systematic review of HCV antibody prevalence and incidence in the Maghreb countries as outlined by the PRISMA guidelines. Meta-analyses were conducted using DerSimonian-Laird random-effect models with inverse variance weighting to pool HCV prevalence estimates among general population groups.

Results

We identified 133 HCV prevalence measures and two HCV incidence measures. Among high risk groups, HCV prevalence ranged between 22% and 94% among people who inject drugs, 20% and 76% among dialysis patients, and 2% and 51% among hemophiliacs. Among intermediate-risk groups, considerable but widely variable HCV prevalence was found. Most common risk factors cited across studies were the duration of dialysis, number of transfusions, and having a history of surgery or dental work. The national HCV prevalence in Algeria was estimated at 0.3% (95%CI: 0.1–0.5), Libya 1.2% (95%CI: 1.1–1.3), Mauritania 1.1% (95%CI: 0–2.3), Morocco 0.8% (95%CI: 0.5–1.2), and Tunisia 0.6% (95%CI: 0.5–0.8).

Conclusions

HCV prevalence in the Maghreb region of the Middle East and North Africa is comparable to that in developed countries of about 1%. HCV exposures appear often to be linked to medical care and are suggestive of ongoing transmission in such settings. Injecting drug use appears also to be a major, though not dominant, contributor to HCV transmission. Further research is needed to draw a more thorough understanding of HCV epidemiology, especially in the countries with limited number of studies. HCV prevention policy and programming in these countries should focus on the settings of exposure.  相似文献   
98.
IntroductionResearchers and policy-makers are interested in the influence that food retailing around schools may have on child obesity risk. Most previous research comes from North America, uses data aggregated at the school-level and focuses on associations between fast food outlets and school obesity rates. This study examines associations between food retailing and BMI among a large sample of primary school students in Berkshire, England. By controlling for individual, school and home characteristics and stratifying results across the primary school years, we aimed to identify if the food environment around schools had an effect on BMI, independent of socio-economic variables.MethodsWe measured the densities of fast food outlets and food stores found within schoolchildren’s home and school environments using Geographic Information Systems (GIS) and data from local councils. We linked these data to measures from the 2010/11 National Child Measurement Programme and used a cross-classified multi-level approach to examine associations between food retailing and BMI z-scores. Analyses were stratified among Reception (aged 4-5) and Year 6 (aged 10-11) students to measure associations across the primary school years.ResultsOur multilevel model had three levels to account for individual (n = 16,956), home neighbourhood (n = 664) and school (n = 268) factors. After controlling for confounders, there were no significant associations between retailing near schools and student BMI, but significant positive associations between fast food outlets in home neighbourhood and BMI z-scores. Year 6 students living in areas with the highest density of fast food outlets had an average BMI z-score that was 0.12 (95% CI: 0.04, 0.20) higher than those living in areas with none.DiscussionWe found little evidence to suggest that food retailing around schools influences student BMI. There is some evidence to suggest that fast food outlet densities in a child’s home neighbourhood may have an effect on BMI, particularly among girls, but more research is needed to inform effective policies targeting the effects of the retail environment on child obesity.  相似文献   
99.
A common overlapping site on the N-terminal IgV-like domain of human carcinoembryonic antigen (CEA)-related cell adhesion molecules (CEACAMs) is targeted by several important human respiratory pathogens. These include Neisseria meningitidis (Nm) and Haemophilus influenzae (Hi) that can cause disseminated or persistent localized infections. To define the precise structural features that determine the binding of distinct pathogens with CEACAMs, we have undertaken molecular modelling and mutation of the receptor molecules at previously implicated key target residues required for bacterial binding. These include Ser-32, Tyr-34, Val-39, Gln-44 and Gln-89, in addition to Ile-91, the primary docking site for the pathogens. Most, but not all, of these residues located adjacent to each other in a previous N-domain model of human CEACAM1, which was based on REI, CD2 and CD4. In the current studies, we have refined this model based on the mouse CEACAM1 crystal structure, and observe that all of the above residues form an exposed continuous binding region on the N-domain. Examination of the model also suggested that substitution of two of these residues 34 and 89 could affect the accessibility of Ile-91 for ligand binding. By introducing selected mutations at the positions 91, 34 and 89, we confirmed the primary importance of Ile-91 in all bacterial binding to CEACAM1 despite the inter- and intraspecies structural differences between the bacterial CEACAM-binding ligands. The studies further indicated that the efficiency of binding was significantly enhanced for specific strains by mutations such as Y34F and Q89N, which also altered the hierarchy of Nm versus Hi strain binding. These studies imply that distinct polymorphisms in human epithelial CEACAMs have the potential to decrease or increase the risk of infection by the receptor-targeting pathogens.  相似文献   
100.
Upon cultivation of chicken lymphoid tumors induced by Georgia isolate of Marek's disease, clusters of refractile rounded cells appeared consistently in the cell cultures. Intranuclear mature, immature, enveloped, and empty herpesvirus-type particles, usually associated with smaller particles, were observed in all rounded cells in the affected areas. Cytoplasmic inclusions containing mature enveloped virus particles were also seen in the rounded cells. Often fibroblasts growing in the vicinity of the cytopathic effect area contained a few herpesvirus-type particles. The original tumors prior to cultivation did not reveal any virus particles, and the virus in infected cultures was always cell-associated. Control cell cultures neither developed the rounded cells nor demonstrated the presence of any type of virus particles.  相似文献   
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